Hi CamielD, Welcome to Microsoft Community.Thank you for posting your inquiry regarding Family Safety.
It's understandable that you'd feel frustrated when something as seemingly straightforward as setting separate screen time limits doesn’t align with your expectations. Unfortunately, the current design of Family Safety ties screen time limits to the account rather than individual devices, which can make setting separate limits challenging.
According to relevant articles, the "device" referred to by the Family Safety service in most cases refers to devices of different types/different platforms, such as Windows devices and Xbox devices.
Set screen time limits across devices - Microsoft Support
An alternative option is to create an additional new Microsoft account for your child and add that new account to your Family Safety Group. We understand that this may not be the most perfect option, but most members of the Answers community work as general support staff rather than product developers. This is the closest alternative we have access to at this time for that purpose.
Similar to you or other community members, we do not have dedicated channels or tools to communicate directly with the product team.
Your ideas and suggestions are essential to improve Microsoft products, but this forum is primarily a technical communication platform and the Microsoft development team will not be active in this forum. If you wish, you can post a question or idea (with as much detail as possible, including pictures, copied videos, etc., if convenient) about Family Safety on the dedicated feedback platform, where a dedicated developer will pay attention and comment on your feedback.
Thanks for your patience and understanding.Best Regards,Kyo.Y - MSFT | Microsoft Community Technical Support